在windows 下记录你操作键盘的所有动作，采用的是键盘钩子，其实没有什么困难的。但是linux下就不行了-Recording in the windows of all the actions your keyboard, using the keyboard hook, in fact, there is nothing difficult. But we would not be under linux

Netfilter是Linux 2.4.x引入的一个子系统，它作为一个通用的、抽象的框架，提供一整套的hook函数的管理机制，使得诸如数据包过滤、网络地址转换(NAT)和基于协议类型的连接跟踪成为了可能。(Netfilter is a subsystem introduced by Linux 2.4.x, which serves as a general, abstract framework that provides a complete set of management mechan